What does the curiosity of this guy towards me mean, why such questions towards me?

This guy I've just met in class started asking quite a few questions about my "love" past.
He asked me about a guy from our school I was friend with but not anymore, he told me "what happened, he was crazy about you and you rejected him i'm sure...", which was a joke but, it surprised me and felt like a compliment.
Also he tried to ask about my past bf, insistently, once he teased me for almost an hour to get the name of my last boyfriend. He also asked a lot of questions about what happened with this guy I jwas friend with...
Well the thing, I don't have a lot of experience so there wouldn't be a lot of information to deliver anyways, I'm just surprised by his curiosity.
Guys, when you're dying to know more about a girl romantic past, and what happened with her past friends of bf, can it mean that you are into her? Why would he be so curious while we've only met 3 weeks ago?

I must precise he is a very nice and well educated guy, a gentleman really, we talk often, he walks me to my bus station when we finish class together (could only because we get along well and to try to male friends, i don't know).